I'm running Excel 2003 under Windows 7 64-bit. Even on a blank spreadsheet, Excel 2003 will lag or freeze up every 10 seconds or so and every time I insert a value in the spreadsheet. I have attempted to turn on manual calculations. What else could be causing this slow down and how can I diagnose this annoying bug?

I've used Office 2003 (including Excel) and I haven't had a slow down of any sort. The only thing that I could think of is that you may have something (a virus perhaps?) running in the background. Have you checked your task manager while it's running?

Why do people always mention viruses and slow-downs in the same sentence? Yes, some viruses can cause a slowing of the system, but compared to other reasons, a virus is hardly the first thing I would mention...
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Matthieu CartierJan 31 '11 at 23:27

The slow down only seems to occur with Excel, not any other, even computationally intensive, programs. In this case, I have scanned the process list and none correspond to any known viruses, and my virus scanner hasn't reported anything. @neurolysis, while I agree it is an often mentioned cause of lag, viruses/malware are often overlooked as the cause since their presence is not immediately obvious.
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adurityFeb 1 '11 at 6:27